Abstract
Adenocarcinoma of the small bowel accounts for 2% of gastrointestinal tumours and 1% of G I cancer deaths. It has a poor outcome despite apparent curative resection.
Primary adenocarcinoma of the jejunum is a rare entity. Due to poor specificity of the symptoms a preoperative diagnosis is very seldom made at an early stage. The survival figures correlate with the stage at presentation, and therefore early and aggressive diagnostic and therapeutic intervention seems indicated to improve the outlook in these patients. We present one such case of jejunal adenocarcinoma due to rarity of this lesion.

Introduction
The small intestinal mucosa makes up about 90% of the total surface of the gastrointestinal tract. However adenocarcinomas rarely arise in this location. Small bowel adenocarcinoma accounts for 2% of gastrointestinal tumours and 1% of gastrointestinal cancer death.1 In the small bowel the jejunum is the commonest site followed by the duodenum and then ileum.1 The patients usually have a poor outcome due to the poor specificity of symptoms and therefore present at a much advanced clinical stage.2 Very often the patients present with intestinal obstruction. We present one such case of jejunal adenocarcinoma due to the rarity of this lesion.³

Case Report

Our patient was a 40 year old lady who had presented with h/o bilious vomiting and passage of black tarry stools since 3 months. The patient on general examination appeared icteric. Total serum bilirubin levels were 8 mg%. Ultrasonography of the abdomen revealed fatty change in the liver with dilatation of the common bile duct. In view of the patients deteriorating clinical condition she was taken up for exploratory laparotomy. Surgery revealed a stricturous growth causing narrowing of the bowel 2 cm distal to the duodenojejunal junction. Two small nodular lesions 1.5 cms apart were also noted in the distal part of the jejunum. The length of the jejunum showing the above lesions could not be resected due to extensive adhesions and the surgery was abandoned. Post operatively the patient developed severe electrolyte imbalance and died after 7 hours due to sever hypokalaemia.

An autopsy was performed. At autopsy the jejunum showed a stricturous growth 1.5 cms from the DJ junction greyish white in colour. The two other nodular growths in lower jejunum were seen to be arising from the mucosa (which showed superficial ulceration) and reaching upto the serosa (Fig. 1). There was no evidence of tumour metastases at any other site. Histopathology of all the three lesions of the jejunum showed features of a well to moderately differentiated adenocarcinoma (Fig. 2).

Fig. 1 : Stricturous growth 1.5 cms from the DJ Junction and two nodular growths in the lower jejunum.	Fig. 2 : Well to moderately differentiated adenocarcinoma (100x)

Discussion

Primary small bowel adenocarcinoma is uncommon and there are very few large studies that have evaluated the prognostic impact of clinical and pathologic parameters.⁴ Our patient presented with symptoms of small bowel obstruction which is one of the commoner modes of presentation. Age, gender, tumour size and growth pattern usually do not affect the survival rate. The mean age at presentation is 59 years (range 37 - 78 years).⁵ Cytogenetic studies of this tumour show deletions of 18 q 21 - q 22, which frequently target the SMAD4 gen. Because of the rarity of the lesion there have been cases where the stricturous growth was initially thought to be tuberculous in aetiology, hence enteroscopy and biopsy have got an important role to play in the definitive diagnosis of high small bowel strictures.⁶ There have been case reports in literature of multifocal primary adenocarcinoma of the jejunum as in our case.⁷ The single most important prognostic indicator in these tumours is the depth of tumour invasion or the stage at the times of diagnosis. The rarity of these tumours and their inaccessibility hinder detection and their surgical resection is more effective than chemotherapy.